The invention relates to a portable power tool having a housing with a connection device for connection of a terminal end of a flexible power supply line.
One problem concerned with power tools of this type is that the handling of the tool is impaired by the power supply line, because normally such power supply lines, either in the form of an electric cable or a pressure air hose, are rather stiff as regards bending. This is the case particularly when using an electric cable having several conductors for power supply as well as for signal exchange with an operation control unit located remotely from the tool.
Moreover, electric power tools are usually equipped with cable re-enforcements for distributing the bending strains, i.e. to prevent too small a bending radius of the cable. Such a device is called "bending relief". However, the relief is just for the cable. The tool operator still experiencies negative effects as the cable becomes even stiffer and the handling of the tool becomes even more awkward.
One way of solving the tool handling problem related to power line stiffness is described in PCT-Application WO 94/11887. The power tool described in this publication is an electric angle nutrunner having built-in sensors for delivered torque, angle of rotation etc., and an awkward handling of this tool is avoided by using a flat type cable which is preformed to a twisted shape in a flex zone adjacent the tool. Still, however, the handling of this tool is somewhat uncomfortable, because bending of the cable will always occur at a certain distance from the tool handle. This means that there will always be a resistive torque on the tool caused by the cable weight or other forces acting on the cable. There will also be undesireable dynamic forces on the tool when articulating the cable during handling of the tool.